Again, there is no change. You are perhaps attributing too much precision to "22kHz" and treating it as different from 22.3kHz. They are the same, with the former simply an approximation of the latter (which itself is not exact, either). The adaptor, again, is not changing any frequencies at all.
And even if it did, a 1.5% difference is too small to matter.

Click to expand...

Ummm ... now I'm really confused, wasn't it sort of emphatically emphasized above that 21.8 KHz was not compatible with 22.3 KHz? Or is that a big enough hair to split.

With that in mind, the ONLY difference I see between EGA & this adapter is that the output is 512x342, rather than 640x350. Is THIS the reason it is being called totally incompatible? I'm also a little confused about those TTL monitors, which were designed for what, MDA/Hercules cards? In which case we're talking 720x350 ... so VERY, very confused. It is a wonder we ever got out of 80s without blowing ourselves up.